He's an excellent interviewer who can work with either humor or gravitas when it's needed. He has been too big for Comedy Central for too long and viewers have wondered for a while now when – not "if" – he would make the jump to a larger network.

Why He Wouldn't: As strong of an interviewer as Stewart is, he's at his best when he's the one talking, not his guest.

His skills as an actor and award show host/singer/dancer make him one of the most talented men in TV. He's always hip, but never too hip for the room. His role on CBS' "How I Met Your Mother" is over, which means he's free, and establishes him firmly as "a CBS guy."

Why He Wouldn't: Harris may be one of the hardest candidates to find serious fault with. If there's room to be found, it may be this: his interview skills are unknown and his sexual preference might be a turn off to some conservative viewers. That's their problem not his, though, and we're not sure how many of those viewers are watching Letterman now, anyway. Harris is a very intriguing candidate.

Virtually everyone loves her, she has sharp comedic skills as both a writer and performer, and she knows what it takes to run a show. Her improv skills are well-honed, so she thinks fast on her feet.

Why She Wouldn't: She's multi-talented, but one of the few things audiences haven't seen her do is conduct interviews. Also, though she does have a strong fan base, that hasn't always translated into actual loyalty: Her NBC sitcom was never a ratings bonanza and can anyone remember going to any of her last few movies? As an "SNL" and NBC Must-See Thursday alumni, she also may be "too NBC" for CBS.

He's almost universally loved, has experience running a major network show and obviously has the chops as a funnyman. His work on the web series "Comedians in Cars Getting Coffee" shows he's also capable as an interviewer.

Why He Wouldn't: Late night these days is high energy, and high energy is one thing Seinfeld isn't.

Why He'd Work: He has an established late night audience and his quirky routine was always a better fit for Dave's type of audience than it was as short-term host of "The Tonight Show."

Why He Wouldn't: His quick departure from "The Tonight Show" could leave some lost-the-job stank on him still, and "Late Show" execs may think it would look bad to have the guy who wasn't good enough for NBC running things at CBS.

The "Family Guy" creator and former Oscar host is edgy, bringing a high "what will he say/do next" factor back to late night. He's also multi-talented as a writer, voice actor, musician, dancer and talking head, so his bits could seemingly go anywhere.

Why He Wouldn't: He may be seen as too edgy, and lacking the proper gravitas to sit down and interview more serious guests (can you really picture Mitt Romney sitting down with McFarlane in 2012)? Also, he has a long history of mean-spirited jokes from "Family Guy" and the Oscars, so some guests may be reluctant to book the "Late Show" if McFarlane is behind the desk.

He's hosted before (HBO's "The Chris Rock Show") and he has that New York vibe that Dave pulled off so well. He obviously knows his way around a punchline, but you can still picture him having a serious interview, when needed.

It's not like it would be the first time he stepped away from late night then came back.

Why He Wouldn't: File this under never-ever-never-never-ever going to happen. CBS isn't going to hire a "Tonight Show" host to take on "Late Show." Besides, Fallon's fresh repackaging at "The Tonight Show" has made Leno's routine look even more stale than it already was.

Why He'd Work: It's not like it would be the first time... Photo-6065473.83256 - SFGate

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Jimmy Kimmel

Why He'd Work:

Dave has always been his hero, so there's no one who probably wants the gig more than Kimmel. And he's an innovator for the new web-savvy, buzz-worthy, late night now being adopted by Fallon and others.

Why He Wouldn't: Kimmel established ABC as a player in late night. If they lose him, they're back to square one. The network will fight to keep him. If he does go, the network likely will hold the rights to some of his best recurring bits, like "This Week in Unnecessary Censorship."

She's quick witted, sharp tongued and knows what it takes to host a nightly show. Plus, she'd be the only woman in major network late night, and there's something to be said for standing out visually.

Why She Wouldn't: Her core audience may be too niche and she could have problems drawing in a broader mainstream audience. She also hasn't shown the kind of polish required to sit down with a head of state for a serious interview – so is she capable?

Why He Wouldn't: Because he just wouldn't – it would be an awful fit. He washed out as a serious interviewer at CNN, so how can anyone expect him to pull off a humorous one in late night? He is in no way a serious contender.

Why He'd Work: He's a known name who knows how to... Photo-6010679.83256 - SFGate

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Seth Meyers

Why He'd Work:

A former SNL writer and "Weekend Update" host, Meyers is a fresh face for NBC's "Tonight Show" follow-up, "Late Night with Seth Meyers." He hasn't been in late night long enough for viewers to slap a label on him, so what his show could become is limitless. With Jimmy Fallon firmly established on "The Tonight Show," he could see the NBC tract to a better time slot as a dead end.

Why He Wouldn't: He's still too much of an unknown quality. Also, as a former 'SNL' player and Lorne Michaels protege, he may seem too much like an "NBC guy" over at CBS. Hiring Fallon's backup to go against Fallon in a potential ratings war also seems like a weak move.

Viewers know him and they're comfortable with him. His celebrity skewering has always been top notch.

Why He Wouldn't: He's fallen to a B-lister, so CBS may feel he doesn't have big enough shoulders to keep the ball rolling after Dave without seeing a drop-off – at least initially. Also, doesn't he kind of feel like Jimmy Fallon's pervy uncle?

He's a known name and an excellent interviewer – maybe the best out there. His work as a judge on "America's Got Talent" has helped rehab his image as someone who can't appeal to women and families. On his satellite radio show, he no longer relies so heavily on bawdy humor, but still retains that "what will he say next" wildcard factor.

Why He Wouldn't: He turned 60 this year and CBS might want to go younger to keep up with the fresh-faced Fallon.

Why He'd Work: He has been on TV for years but still seems... Photo-6069885.83256 - SFGate

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Anderson Cooper

Why He'd Work: He's a strong interviewer and has a surprisingly well-developed sense of humor. On his show and in social media, he has shown he is good at interacting with fans and despite being a CNN personality, doesn't come off as stuffy.

Why He Wouldn't: He can't keep up with Fallon or Kimmel in the comedy department.

Why He'd Work: He has followed Letterman on the "Late... Photo-1156923.83256 - SFGate

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Regis Philbin

Why He'd Work:

Everyone loves him, he has an excellent sense of humor and is a tremendous interviewer.

Why He Wouldn't: No network likes instability in their lineup, especially somewhere as crucial as late night. Philbin is already 82, so CBS may worry it would be back hunting for a new host in a few short years.

Why He'd Work: Viewers would tune in to see what happened... Photo-6115173.83256 - SFGate

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Jon Hamm

Why He'd Work: "Mad Men" is ending, so he's seemingly free. His more serious work on the show belies how funny he truly is, which has been better displayed in guest spots on "30 Rock," "SNL" and on various comedy podcasts.

Why He Wouldn't: He's an actor and his future is bright there. Taking over a late night spot would require too much time to allow him to pursue acting roles full-time.

Why He'd Work: "Mad Men" is ending, so he's seemingly free. His more serious work on the show belies how funny he truly is, which has been better displayed in guest spots on "30 Rock," "SNL" and on various

Why He Wouldn't: The plot of an episode of his FX comedy "Louie" centered around C.K. replacing a retiring Letterman, but the reasons why it didn't make sense on the fictional show are the same reasons it doesn't make sense in real life: He's not polished enough for the gig – a likable every man but not the kind of "cool factor" you expect from a late night host.

Why He'd Work: His comedy is some of the smartest going... Photo-6015986.83256 - SFGate

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Alec Baldwin

Why He'd Work:

His inherent prestige would immediately make him the big dog of late night – a man among boys. He has a strong enough sense of humor to carry the comedic parts of the show and his "SNL" appearances prove he can deliver a monologue.

Why He Wouldn't: He's controversial, but not in a good way. More in the "stick your foot in your mouth" kind of way. A Republican candidate for president isn't going to sit down with Baldwin and feel like he's getting a fair shake.